OBJECTIVE: The objective of this study is to compare the immediate results of patients undergoing on-pump versus off-pump coronary artery bypass graft (CABG) surgery. METHODS: From January 2007 to January 2009, 177 patients underwent CABG, being 92 off-pump and 85 onpump. We evaluated the demographics, preoperative risk factors, preoperative functional class and risk assessment by the EuroSCORE. The postoperative evolution was compared between groups. RESULTS: The mean number of grafts per patient was 2.48 ± 0.43 in off-pump group and 2.90 ± 0.59 in on-pump group. In the off-pump group, 97.8% of patients received an internal thoracic artery graft, while on-pump group the percentage was 94.1% (P = 0.03). The rate of complete revascularization was similar in both groups. In off-pump group, the circumflex artery was revascularized in 48.9% and 68.2% in the onpump group (P = 0.01). Hospital mortality was 4.3% and 4.7%, respectively in the off-pump group in the on-pump group (P = 0.92). Off-pump group had fewer complications in relation to perioperative myocardial infarction (P = 0.02) and use of intra-aortic balloon pump (P = 0.01). CONCLUSION: The off-pump CABG is a safe procedure with hospital mortality similar to that observed in on-pump CABG, with lower rates of complications and less need for intra-aortic balloon.